Mercruiser v8 tale of woe - advice needed.

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Mikehp0

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I’m trying to help my very busy brother-in law get his 2001 vintage 22' Sea Ray boat fixed and running. It has a 5.0 V8 Mercruiser with the early EFI fuel injection system rather than the later multi-point MPI system.

Poor Mark has had nothing but bad luck, starting with a near sinking incident in the entrance to Poole Harbour when the engine ingested sea water.

Mark entrusted repairs to a recommended engineer who turned flaky and then did a runner. He gave Mark what sounded like sensible advice – the guy didn’t have the time to rebuild a damaged engine mid-season and suggested it would be much quicker and just as cost effective to fit a reconditioned engine. Mark paid him up front. The rusty engine was removed and months later a shinier engine was put back in but the guy disappeared before completing the electrical and peripheral hook-ups. Several components disappeared, including the ECU.

When Mark couldn’t get this guy to finish the job, he towed the boat to a one-man band Devon based engineer that had been recommended. This guy spotted all sorts of problems with the previous engineer’s work and allegedly put them all right by completely stripping the new engine. He supplied a used ECU. However, whilst it would run nicely at tickover, he couldn’t get the engine to run properly under load. He admitted he didn’t know anything about the fuel injection system and wasn’t sure that the ECU he’d supplied was right for the engine. He recommended taking off the fuel injection system, removing the various sensors and swapping back to a simple carburettor fuel system but by this point Mark had lost confidence, paid the guy and towed the boat home.

A bit of googling has confirmed that the ECU on the boat is a V6 engine unit.

We then found a “Mercruiser Specialist” who said they had old ECUs on the shelf and might be able to help. We towed the boat to them and now they've had a good look, they’ve thrown their hands up in horror. They can’t identify the engine - the “new” engine has had its serial number ground off.. Removing a bit of shiny black paint reveals green paint. Is it really a Mercruiser engine? Unless they can identify the engine, they are telling Mark not to risk buying in a new ECU from the USA.

We now don’t know what to do and we’re looking for good advice . The boat is worth £10-£15k maximum but is in lovely condition. The options seem to be:

1. Risk buying a new v8 ECU from the US at nearly £2k but there are several different versions so we waste time and money getting
the "mercruiser specialists" to fit each one and test.
2. spend £2k to strip the injection system and fit carburettors to at least get it running.
3. Scrap the whole engine and fit an £8k replacement with known provenance and a warranty– maybe a later MPI unit.
4. Scrap the boat - sell it for spares.
 
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Try chera Marine in west yorks

I don't know if they are any good but advertise recon engine with 12 month warranty

I wouldn't scrap it

Good luck

Ash
 
You could try posting your story on the iBoats forum (https://forums.iboats.com/forum/eng...ance/mercruiser-i-o-inboard-engines-outdrives) complete with some pictures and a more detailed description of the engine. Some of the posters on there are real Mercruiser geeks. They should be able to identify the engine and which ECU's will work.
Once you have the engine identified, buy (carefully) a secondhand ECU from one of the marine scrapyards on US eBay.
 
Mikehp0 said:
I’m trying to help my very busy brother-in law get his 2001 vintage 22' Sea Ray boat fixed and running. It has a 5.0 V8 Mercruiser with the early EFI fuel injection system rather than the later multi-point MPI system.

Poor Mark has had nothing but bad luck, starting with a near sinking incident in the entrance to Poole Harbour when the engine ingested sea water.

Mark entrusted repairs to a recommended engineer who turned flaky and then did a runner. He gave Mark what sounded like sensible advice – the guy didn’t have the time to rebuild a damaged engine mid-season and suggested it would be much quicker and just as cost effective to fit a reconditioned engine. Mark paid him up front. The rusty engine was removed and months later a shinier engine was put back in but the guy disappeared before completing the electrical and peripheral hook-ups. Several components disappeared, including the ECU.

When Mark couldn’t get this guy to finish the job, he towed the boat to a one-man band Devon based engineer that had been recommended. This guy spotted all sorts of problems with the previous engineer’s work and allegedly put them all right by completely stripping the new engine. He supplied a used ECU. However, whilst it would run nicely at tickover, he couldn’t get the engine to run properly under load. He admitted he didn’t know anything about the fuel injection system and wasn’t sure that the ECU he’d supplied was right for the engine. He recommended taking off the fuel injection system, removing the various sensors and swapping back to a simple carburettor fuel system but by this point Mark had lost confidence, paid the guy and towed the boat home.

A bit of googling has confirmed that the ECU on the boat is a V6 engine unit.

We then found a “Mercruiser Specialist” who said they had old ECUs on the shelf and might be able to help. We towed the boat to them and now they've had a good look, they’ve thrown their hands up in horror. They can’t identify the engine - the “new” engine has had its serial number ground off.. Removing a bit of shiny black paint reveals green paint. Is it really a Mercruiser engine? Unless they can identify the engine, they are telling Mark not to risk buying in a new ECU from the USA.

We now don’t know what to do and we’re looking for good advice . The boat is worth £10-£15k maximum but is in lovely condition. The options seem to be:

1. Risk buying a new v8 ECU from the US at nearly £2k but there are several different versions so we waste time and money getting
the "mercruiser specialists" to fit each one and test.
2. spend £2k to strip the injection system and fit carburettors to at least get it running.
3. Scrap the whole engine and fit an £8k replacement with known provenance and a warranty– maybe a later MPI unit.
4. Scrap the boat - sell it for spares.
Click to expand...

If guess that Your do called rebuilt engine if from Chera marine , I’m afraid you may have leaned the hard way as I’ve had first hand experience of thrtevdo called re condition engines , the 2 I was asked to sort out were built from pistons I’d have thrown in the scrap bin , there wasn’t any new parts inside the engines at all just new gaskets , they didn’t fit new bearings . Both engines had to be removed and fully rebuilt by a dealer . Cost another 26 k to sort out .
Do not use chera marine . I think there was a post on here about them a while back . Your engine may be the Ford based V 8, which may have green primer .
 
jimmy_the_builder said:
It's not that difficult - 'do called' = 'so called' (the d is next to the s...) and 'thrtevdo called ' = 'their so called'. Any better?
Click to expand...
Thank you.. but the bit I was struggling to understand was why Paul was casting aspersions on another marine engineering business. We've never dealt with that business - the guy that rebuilt Mark's engine is in Devon and seems to have done a pretty competent job on the mechanical elements of the job. Whilst writing, we're very grateful to Tom of Tompa Marine (as kindly recommended in posts above) who emailed a reply within minutes late last night containing very positive and helpful information.
 
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Mikehp0 said:
Thank you.. but the bit I was struggling to understand was why Paul was casting aspersions on another marine engineering business. We've never dealt with that business - the guy that rebuilt Mark's engine is in Devon and seems to have done a pretty competent job on the mechanical elements of the job. Tom of Tompa Marine (as kindly recommended in posts above) emailed a reply within minutes and has been very positive and helpful.
Click to expand...

Aha sorry, your post read like you couldn't understand his typing. No probs. I obvs can't speak for Paul, but I think he's talking about the original supply of the reconditioned engine, not the subsequent rebuild in Devon.
 
jimmy_the_builder said:
Aha sorry, your post read like you couldn't understand his typing. No probs. I obvs can't speak for Paul, but I think he's talking about the original supply of the reconditioned engine, not the subsequent rebuild in Devon.
Click to expand...

The young guy that supplied the supposedly reconditioned engine then ran off with Mark's money and ECU was a Poole based "one man and van" business. I won't name him because he was a nice, competent guy who, according to rumours we have heard but can't substantiate, has gone off the rails due to the kind of "personal health problems" that can enter the body via the nostrils. If he sorts all of that out, I wouldn't want to ruin his future career - I don't think he's trading and therefore messing anyone else around at present because his website has gone offline.

Incidentally, two other people in the marine engineering trade that I know well recommended Chera Marine. I emailed them late last night and I had an excellent chat with the main guy there when he called me earlier today. He is very knowledgeable but sadly, he can't help - he only supplies reconditioned short or long engines rather than the ECU and sundry electronic parts that we probably need.
 
jimmy_the_builder said:
Aha sorry, your post read like you couldn't understand his typing. No probs. I obvs can't speak for Paul, but I think he's talking about the original supply of the reconditioned engine, not the subsequent rebuild in Devon.
Click to expand...

Thanks jimmy indeed I am .

I’ll keep out this one from now on as I know nothing after 30 years in the trade .
 
Jeez, this is a nightmare. Few comments from me below, but my best advice is to ask the yanks on iboats forum. They are superb with these engines.
Ok, so I’ve had loads of the gm v engines and what I can say is that if this is a Merc engine and a 5.0, you need the right ecu to match. Anything other has the fueling totally wrong.
The green paint would suggest it’s neither a VP or a Merc engine but both are based on the very common GM auto engine and 99% the same. If it’s a auto based engine you should get it to work with the right ecu. Have you looked down near the starter for a serial number ?
Converting to carbs might be an option, but the likely cost you would be as well just getting a used complete engine. Or a crate block engine from the stares.
Anyway. 100% get on iboats and explain the situation. These guys will at least help you identify it. A guy called All dodge in particular.
 
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